Flexible airtight stranded wire

ABSTRACT

The disclosure relates to a flexible airtight stranded wire for electrical interconnection between chambers wherein it is necessary that gases do not travel between chambers. The wire is formed from standard stranded wire, a short length of stranded or unstranded wire is tightly wound around one section of the wire and the wound length of wire is soldered to the stranded wire the solder passing into and entirely across the stranded wire to provide a gas tight seal therethrough. The soldered wire is then placed in a mold and stretched whereupon insulation is molded thereon, the area over the wound length of wire and solder having a greater cross-section than the remainder of the wire. The wire is secured in a bulkhead, the insulation making an airtight seal therewith.

United States Patent 1 1 Glover FLEXIBLE AIRTIGHT STRANDED WIRE [75] Inventor: Douglas Wade Glover, Harrisburg,

[21] App]. No.: 357,970

[52] U.S. Cl. 174/152 R, 174/23 R [51] lint. Ci. H0111) 117/26, l-l0lb 7/00 [58] Field of Search 174/18, 20, 22 R, 23 R, 174/65 R, 151,152 R [56] References Cited UNITED STATES PATENTS 658,192 9/1900 Sutter 174/23 R X 1,267,832 5/1918 Wilkinson 174/23 R 1,788,485 1/1931 Gunderson 174/152 R UX 1,956,357 4/1934 Leib 174/152 R 2,563,829 8/1951 Fitzgerald et a1. 174/23 R 2,624,286 1/1953 Smith 174/23 R 2,890,268 6/1959 Berry 174/23 R X 2,898,396 8/1959 Watson 174/23 R X Primary Examiner-Laramie E. Askin Attorney, Agent, or Firm-Gerald K. Kim

[57] ABSTRACT The disclosure relates to a flexible airtight stranded wire for electrical interconnection between chambers wherein it is necessary that gases do not travel between chambers. The wire is formed from standard stranded wire, a short length of stranded or unstranded wire is tightly wound around one section of the wire and the wound length of wire is soldered to the stranded wire the solder passing into and entirely across the stranded wire to provide a gas tight seal therethrough. The soldered wire is then placed in a mold and stretched whereupon insulation is molded thereon, the area over the wound length of wire and solder having a greater cross-section than the remainder of the wire. The wire is secured in a bulkhead, the insulation making an airtight seal therewith.

9 Claims, 7 Drawing Figures 1 FLEXIBLE AIRTIGHT STRANDED WIRE This invention relates to a flexible airtight stranded wire and, more specifically, to a flexible electrical wire capable of passing between two chambers while providing an airtight seal between chambers both around and through the wire.

It is often necessary to provide a flexible electrical interconnection between a pair of chambers wherein it is desired to maintain the gases in each chamber isolated from each other. This has provided a problem in the prior art because flexible electrical wire is of the stranded type and therefore allowed gases, such as at different pressures, to pass between chambers by passing between the strands of wire. There has also been leakage due to movement of the wire relative to its insulation, thereby breaking the bond between the wire and the insulation and allowing gases to pass between the wire and the insulation.

In accordance with the present invention, the above noted problems are overcome and there is provided a flexible stranded electrical wire which prevents gases from passing therethrough, either between the strands or between the insulation and the strands. This is accomplished by providing a bump on the stranded wire, such as by wrapping a loop of wire therearound and then soldering the loop of wire to the stranded wire and also allowing the solder to flow into the stranded wire beneath the loop to provide a wall of solder between strands and prevent the passage of gases between the strands. The soldered wire is then placed in a mold and stretched, whereupon insulation in the form of silicone rubber or the like is coated over the stranded wire, the insulation over the bump having a greater cross-section than that at other regions along the wire. The enlarged region of insulation provides a surface for making an airtight seal around the exterior of the insulation whereas the bump within the insulation prevents axial and lateral movement of the wire relative to the insulation to minimize rupture of the bond between wire and insulation.

It is therefore an object of this invention to provide a flexible electrical wire which prevents passage of gases therethrough.

It is a further object of this invention to provide a flexible electrical wire which provides airtight electrical connection between a pair of chambers at different pressure.

The above objects and still further objects of the invention will become immediately apparent to those skilled in the art after consideration of the following preferred embodiments thereof, which are provided by way of example and not by way of limitation, wherein:

FIG. 1 is a perspective view of a stranded wire before placing the wire loop thereabout;

FIG. 2 is a perspective view of a stranded wire with a wire loop therearound and solder;

FIG. 3 is a cross-section of the wire of FIG. 2 with insulation therearound;

FIG. 4 is an enlarged view of a portion of FIG. 3;

FIG. 5 is a view of the wire of FIGS. 3 and 4 prior to assembly into a wall or bulkhead;

FIG. 6 is a view as in FIG. 5 but after assembly; and 6 FIG. 7 is a second embodiment of the invention.

Referring now to FIG. ll, there is shown a stranded wire ll of standard type and a small length of wire 3 which can be solid or stranded. The wire 3 is wrapped around the wire l in the form of a helix or the like as shown in FIGS. 2 and 4. The wire 3 is then soldered to wire I, the solder 5 being permitted to flow into the stranded wire I in the region immediately surrounded by the wire 3 to provide a continuous wall of wire strands from wire l and solder completely across the wire l. The continuous wall prevents the passage of gases along the wire 1 between the strands thereof.

The wire as shown in FIG. 2 is then placed in a mold and stretched along its axis, whereupon an insulating material, such as silicone rubber is placed in the mold. The mold is shaped to provide a sleeve 7 of insulation with an enlarged region 9 over and surrounding the bump formed by the wire 3 and solder 5 as shown in FIGS. 3 and 4. The completed insulated wire is prevented from movement along its axis within the insulation due to the bump, this minimizing the possibility of rupture of the bond between the wire 1 and the insulation 7 and also minimizing the possibility of gases escaping along the wire between the wire 1 and the insulation 7.

Referring now to FIG. 5, installation of the wire of FIGS. 3 and 4 is shown. There is shown a wall or bulkhead 11 which separates two chambers at different pressures. The wall 11 includes a recess 21 for receiving the enlarged portion 9 of the insulation, an aperture 23 through which the insulation 7 passes and a pair of threaded grooves 13 for receiving screws 19. The insulation 7 passes through aperture 23, the insulation portion 9 being positioned in recess 21. A washer l5 having apertures 17 through which screws 19 pass abuts the insulation portion 9 at its end remote from wall 11, the wire 7 passing through an aperture 25 in the washer. This assembly is shown in FIG. 5. In operation, the screws 19 are threaded into the threaded grooves 13, driving the washer 15 against the insulation portion 9 and deforming it as shown in FIG. 6. This provides a gas tight seal between the insulation portion 9, the aperture 21 and the wall ll. It is therefore apparent that gases are now prevented from passing across wall 111 either around or through the wire.

Referring now to FIG. 7, there is shown a second embodiment of the invention. Here the insulation portion 9' is at a right angle, this being accomplished by providing the right angle bend in the mold and providing a mold with the shape shown. This embodiment is utilized when a right angle turn of the wire is required.

Though the invention has been described with respect to specific preferred embodiments thereof, many variations and modification will immediately become apparent to those skilled in the art. It is therefore the intention that the appended claims be interpreted as broadly as possible in view of the prior art to include all such variations and modifications.

-What is claimed is:

l. An airtight stranded wire which comprises a. a stranded wire b. an annular member surrounding a portion of said wire in intimate contact therewith to form a bump thereon,

c. a continuous wall of solder substantially normal to the axis of said wire extending between and around the strands of said wire within the area defined by 3 4 the annular member to provide an airtight seal and means bearing against one end of said portion of along the axis of said wire, and the insulation about the protuberance for comd. insulation means surrounding said wire and said pressing it against the wall about said opening to annular member and bonded thereto, form a seal.

e. said insulation means including insulation of pre- 5 4. Structure according to claim 3 wherein the condetermined first cross-section over said annular ductor is a flexible stranded wire and the protuberance member and insulation of predetermined second is an annular loop soldered to the wire. cross-section less than said first crosssection along 5. Structure according to claim 3 wherein the con the remainder of said wire. ductor is a flexible stranded wire with the interstices 2. An airtight stranded wire as set forth in claim 1 between the strands within the area encompassed by wherein said annular member is a turn of wire in a one the protuberance filled by a solid wall of solder.

plane substantially normal to said stranded wire. 6. Structure according to claim 5 wherein the protu- 3. Structure for providing an airtight passageway for berance is soldered to the wire. a flexible conductor passing through an opening in a 7. Structure according to claim 5 wherein the protuwall, wherein the conductor is provided with an annuberance is a single turn of wire in a single plane normal lar protuberance thereabout, to the wire axis.

insulation bonded to the conductor and protuber 8. Structure according to claim 3 wherein the protuance, berance is soldered to the wire. the portion of the insulation about the protuberance 9. Structure according to claim 8 wherein the protubeing of greater diameter than that about the reberance is a single turn of wire in a single plane normal maining portion of the conductor and that of the to the axis of the wire.

opening, 

1. An airtight stranded wire which comprises a. a stranded wire b. an annular member surrounding a portion of said wire in intimate contact therewith to form a bump thereon, c. a continuous wall of solder substantially normal to the axis of said wire extending between and around the strands of said wire within the area defined by the annular member to proviDe an airtight seal along the axis of said wire, and d. insulation means surrounding said wire and said annular member and bonded thereto, e. said insulation means including insulation of predetermined first cross-section over said annular member and insulation of predetermined second cross-section less than said first crosssection along the remainder of said wire.
 2. An airtight stranded wire as set forth in claim 1 wherein said annular member is a turn of wire in a one plane substantially normal to said stranded wire.
 3. Structure for providing an airtight passageway for a flexible conductor passing through an opening in a wall, wherein the conductor is provided with an annular protuberance thereabout, insulation bonded to the conductor and protuberance, the portion of the insulation about the protuberance being of greater diameter than that about the remaining portion of the conductor and that of the opening, and means bearing against one end of said portion of the insulation about the protuberance for compressing it against the wall about said opening to form a seal.
 4. Structure according to claim 3 wherein the conductor is a flexible stranded wire and the protuberance is an annular loop soldered to the wire.
 5. Structure according to claim 3 wherein the conductor is a flexible stranded wire with the interstices between the strands within the area encompassed by the protuberance filled by a solid wall of solder.
 6. Structure according to claim 5 wherein the protuberance is soldered to the wire.
 7. Structure according to claim 5 wherein the protuberance is a single turn of wire in a single plane normal to the wire axis.
 8. Structure according to claim 3 wherein the protuberance is soldered to the wire.
 9. Structure according to claim 8 wherein the protuberance is a single turn of wire in a single plane normal to the axis of the wire. 